On the market today, there are a number of inhalers for powdery substances, most of which are so-called multidose—inhalers. Those currently marketed are relatively large and clumsy in their execution, which means that storing them in clothes/handbags and also the handling of them are not very user-friendly. Another problem is that they do not always deliver the precise and intentional dose and that unintentional feeding forward of new dos is possible—which means that the user, by mistake, may receive double or even larger dos. When the dose is loaded in position to be inhaled, the user can accidentally blow air into the multi-dose inhaler so that moisture can accumulate and cause the powdered substance to get stuck together. Further, the known multidose-inhalers, consists of many parts, making them complicated and thus expensive to manufacture and thus expensive to buy for the end user. A large number of components also increase the number of confounding factors. At a given quality level the number of possible errors, in principle, increases linearly with the number of parts. And it is desired that the inhaler contain many doses, for example, 60 doses or more, to increase comfort for the user.
There have been many attempts to construct multidose—inhalers that solve these problems. The following, inhalers U.S. Pat. No. 6,273,085, U.S. Pat. No. 7,275,538B2, U.S. Pat. No. 6,871,647, U.S. Pat. No. 7,395,821B2 and US2009205657A1 are examples of such attempts. A disadvantage is that they have at least nine or more parts and some form of closed encapsulation of the powdery substance to be inhaled. In order to expose the substance, the encapsulation must be pierced, a seal rolled up, torn of or similar in order to make the powdery substance free for inhalation. This encapsulation or rather, the mechanism needed to break the seal, is the crucial factor that requires a number of individual parts and makes the multidose-inhaler relatively large and unwieldy. These problems are solved by the present invention.
U.S. Pat. No. 6,273,085 discloses an inhaler with a separate powder cartridge. The cartridge comprises a disc having axial bores constituting the powder chamber. On the top and bottom there is a seal enclosing the holes in the disc and thus seals the powder chamber. An upper and lower spring washer creates the sealing pressure. Thus, five parts are used, only for the function to contain the powder chamber. In the present invention, two parts are used for the same function, the dose ring and the upper housing portion. In the present invention the upper housing portion constitutes one of the two parts to form an enclosed powder chamber. The present invention uses two parts compared to the prior known patent's five parts. The fewer parts gives lower manufacturing costs, lower assembly costs and fewer confounding factors.
U.S. Pat. No. 7,275,538B2 discloses an inhaler with powder chambers, in the shape of cylinders, which are placed one after another in a disk that uses a piercing device with a needle to penetrate one chamber at a time in order to expose the content of the chamber and thus make it possible to inhale its contents. Each chamber is advanced, one at a time, after which it is pierced from the inner part of the disk. The piercing arrangement means that the design height is approximately 11 times as high as the air channel's height. Powder can get stuck on the needle that penetrates through both Chambers, powder can also end up in the aerodynamic shadow under or behind the parts of the penetrated foil that folds inwards in the powder chamber when its penetrated, and the foil can also contaminate the powder. The solution hampers production because the chambers are to be filled with powder and then sealed on both the inner and the outer part of the disk. The numbers of parts are at least nine.
U.S. Pat. No. 6,871,647 describes a device that consists of three times as many parts as the present invention. In order to expose the dose that will be inhaled from the chambers, an encapsulation/tape needs to be “rolled up” or “peeled” off. This complicated method of opening the chambers also endangers that parts of the encapsulation material will be mixed with the substance in the powder chamber and thus contaminate it. The inhaler is considerably thicker and in every way bigger in volume and therefore more bulky in its design than the present invention and, therefore, more cumbersome to store and manage.
U.S. Pat. No. 7,395,821B2 discloses a device, which consists of twelve parts where the covering tape, which is arranged on the chambers with medicament, is to be pierced and then inhaled through the “needle” used for penetration. Contamination of the substance to be inhaled is therefore at risk and also that the powdery substance in the powder chamber, may end up in an “aerodynamic shadow” i.e. that not all of the available dose is inhaled since the powder can get caught on the needle that penetrated the sealed chamber and also end up outside of it, during inhalation. The feed forward of doses and the management of the inhaler at inhalation also requires that two hands are used. This is because the upper and lower parts needs to be rotated in opposite directions to forward a new dos and that a “pin” needs to be pressed in order to penetrate the covering sealing in which the substance to be inhaled is located. This inhaler too is considerably thicker and in every way bigger in volume and therefore more bulky in its design than the present invention and, therefore, more cumbersome to store and manage.
US2009205657A1 describes a device which contains twice as many parts as the present invention, as well as where the tape covering the powder chambers, must be drawn away, pierced, pulled apart (“blisters”), etc., to enable the user to inhale the powdery substance. Thus the design uses a completely different sealing solution than the present invention, resulting in the above-described risk of contamination. These sealing solutions also means that space has to be spent for the opening mechanism that is needed to expose the powder to be inhaled. That in turn means that the size of multidose-inhaler inevitably will become larger in size than the present invention, because the method that is used in the present invention, to expose the powdery substance, eliminates the necessity of such a mechanism. Even this famous inhaler is considerably thicker and larger in size, and therefore more bulky in its design than the present invention and, thus, more cumbersome to store and manage.
U.S. Pat. No. 7,571,724 discloses a design with two dosage rings, which are placed one over another. Here, the diameter—size becomes a problem when the number of doses increases, and also the inhaler thickness, which will make it difficult to use and impractical. This solution with two dosage rings superposed, provides a large and unwieldy inhaler.
WO2009102273 discloses a dose ring with containers with an opening arrangement, which is made to open each respective powder chamber. The solution refers mainly to the opening arrangement used to expose the doses of each powder chamber. An inhaler with the described arrangement will be considerably larger in size when the number of doses approaches or exceeds 60 doses.
U.S. Pat. No. 7,571,724 and WO2009102273 thus shows structures that use dose rings, but the dose rings does not hold a sufficient number of doses if the size or thickness of the inhaler shall be kept to a reasonable and user-friendly level. Prior art does not display any solution that demonstrate n inhaler with a dose ring that is small, flexible and easy to carry along, that will fit many doses and yet is inexpensive to produce.